In any number of commercial and other applications, such as agricultural, oil exploration, mining, geological, and infrastructure projects, mobile vehicle navigation, and so on, it would be useful to be determine the position of a navigation receiver or other object with a high level of precision, such as 10 cm, 5 cm, or 2 cm, directly from satellite navigation signals, with respect to a global reference frame using precise point positioning (PPP) or other absolute mode of navigation.
In navigation systems that use a differential mode of navigation, such as real-time kinematic (RTK) based systems, base station receivers (often called base stations), located at surveyed positions, periodically broadcast satellite data to moving object receivers. Moving object receivers combine their own phase measurements with the ones received from the base station, and use that information plus the position of the base station to determine their own position. However, the use of differential modes of navigation is not practical in many settings, due to either the cost of such systems, the lack of base stations positioned sufficiently close to the position(s) of the moveable objects whose position needs to be determined with high precision in real time, or difficulties with reliable signal transmission of information from the local base station(s).
Navigation systems using absolute modes of navigation typically use standard point positioning (SPP) or precise point positioning (PPP). In absolute mode navigation systems, a moveable object's coordinates are determined with respect to a global reference frame, using satellite navigation signals received from multiple navigation satellites. To quickly and accurately determine their positions in the global reference frame, navigation receivers need accurate and up to date information on the orbits, clocks, and satellite-specific signal transmission delays of the navigation satellites from which satellite navigation signals are received.
It would be highly desirable to provide a system and method that determines improved navigation satellite correction information so as to enable navigation receivers to achieve higher levels of position determination accuracy using an absolute mode of navigation.